borgmatic/docs/_includes/components/external-links.css

/* External links */
a[href^="http://"]:not(.minilink):not(.elv-externalexempt),
a[href^="https://"]:not(.minilink):not(.elv-externalexempt), 
a[href^="//"]:not(.minilink):not(.elv-externalexempt) {
	text-decoration-color: inherit;
}
/* External link hovers */
a[href^="http://"]:not(.minilink):not(.elv-externalexempt):hover,
a[href^="https://"]:not(.minilink):not(.elv-externalexempt):hover, 
a[href^="//"]:not(.minilink):not(.elv-externalexempt):hover {
	text-decoration-color: #00bcd4;
}